Is Teflon dangerous?

I had a quick look around pubmed, an aggregator of biological and medical literature, and found very little in the way of actual scientific evidence for teflon toxicity under 500C. In fact, teflon is still widely in use in surgery and can be left inside the body for tens of years.

This does not mean that improper operation (such as overheating to the point of thermolysis) cannot result in compounds you would rather not have in your food. It will also ruin the pan. Don't do it.

I wouldn't put too much faith in articles you read on the internet or otherwise. Teflon poisoning is the least of your worries in a kitchen, the simple dangers associated with hot oil and boiling water far outweigh such trivialities. The fact that professional chefs, chemists and the majority of food safety experts do not worry is a good indicator that they're safe.

I am more interested in your induction hobs and this pan that isn't heating up. Some pans are not compatible with induction hobs, the electromagnetic induction doesn't work in the right way. It might be that your pan is simple incompatible with your hobs.

Well, I read the same several times, and it seems that some toxic elements appear at high temperatures, above 250C.

More can be found here

As long as you are using teflon pans in their intended role, there is no problem. Once the non-stick surface reaches a certain temperature, it starts to release fumes. For an adult human in a well ventilated kitchen, the danger from these is still extremely low.

Don't leave a non-stick pan sitting empty on an active burner.
Don't use a non-stick pan for deep-frying.
Don't use metal utensils (for lifespan of the pan, not danger to you).

Titanium is non-ferrous. Induction works through magnetic fields. If your pan was solid titanium I wouldn't expect it to work at all on an induction range. Since it is working slowly, there must be some other magnetic material underneath or inside the pan, but not enough to heat it properly.

For an induction range, you really need steel or iron pans. Solid aluminum and copper are also non-ferrous and won't work. From my understanding, the best pan is a tri-ply 18/10 steel pan. It has durable steel surfaces, and a layer of aluminum sandwiched in the middle to help distribute heat evenly through the pan. You can use pans with a non-stick surface as long as the base material is ferrous.

Teflon is an inert substance at all but the highest (making pizza maybe) temperatures. Dupont states that it becomes unstable above 260 Celsius or 500 Fahrenheit. Pyrolysis (breaking down of organic compounds in the absence of oxygen) is said to be detectable at 200 C/ 390 F.

Teflon is a result of a mistake by some chemists while trying to come up with an alternative refrigerant to those used at the inception of refrigeration (sulfur dioxide, poison, and anhydrous ammonia, stinky). Their task was to come up with an odorless, non-toxic gas which wouldn't stink or poison people, not conduct electricity, and still work well. Some of the cheap pots and pans I used a few decades ago would sometimes cast off small flakes of Teflon into my food (really skrinchy in the teeth), and I don't like the way Teflon cookware browns food, so I don't own but a small pot I use to make rice in.

Apparently the aluminium that is found under the teflon coating is highly reactive and if you scratch the surface with a metal utensil, the aluminium will get exposed. Some pans of course have a thicker teflon coating than others.

If you heat teflon cookware up to temperatures above 500°F for a few minutes, it releases toxic gasses which will kill birds. See this article and this one. The second says that even teflon at 400°F can kill sensitive birds. I expect that these gasses aren't good for people, either.

But according to the second article above, if you keep your teflon cookware under 400°F, it's safe.

If you cover your floor in Teflon you are more likely to slip…

However I have never heard of any real risk of using Teflon as indented.